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Abstract The advancement of clean energy and environment depends strongly on the development of efficient catalysts in a wide range of heterogeneous catalytic reactions, which has benefited from transmission electron microscopic techniques in determining the atomic‐scale morphologies and structures. However, it is the morphology and structure under the catalytic reaction conditions that determine the performance of the catalyst, which has captured a surge of interest in developing and applying in situ/operando transmission electron microscopic techniques in heterogeneous catalysis. The major theme of this review is to highlight some of the most recent insights into heterogeneous catalysts under the relevant reaction conditions using in situ/operando transmission electron microscopic techniques. Rather than a comprehensive overview of the basic principles of in situ/operando techniques, this review focuses on the insights into the atomic‐scale/nanoscale details of various catalysts ranging from single‐component to multicomponent catalysts under heterogeneous catalytic, electrocatalytic, and photocatalytic reaction conditions involving both gas–solid and liquid–solid interfaces. This focus is coupled with discussions of the correlation of the atomic, molecular, and nanoscale morphology, composition, and structure with the catalytic properties under the reaction conditions, shining light on the challenges and opportunities in design of nanostructured catalysts for clean and sustainable energy applications.
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Homogeneous and Heterogenous Architectures for Electrocatalyis
Catalysts are central to energy conversion in biology and technology; they provide low-energy pathways for steering chemical transformations and are used in applications ranging from manufacturing fuels and fine chemicals to controlling the bioenergetic reactions essential to all living organisms. Accordingly, the study of homogeneous molecular catalysts, including porphyrins, has provided researchers significant insights regarding the mechanisms and structure−function relationships governing myriad catalytic processes, as well as design principles for further improving the performance of human-engineered catalysts. Our research group has recently reported on the favorable catalytic properties of piextended porphyrins for hydrogen evolution, demonstrating the promise of extended macrocycles as a design element and structural motif for preparing electrocatalysts. The pi-extended architecture provides an alternative strategy, compared to using electron-withdrawing or electron-donating functional groups, for adjusting the redox properties of a molecular catalyst and thus a promising avenue for catalyst design warranting further analysis.
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- Award ID(s):
- 1653982
- PAR ID:
- 10128534
- Date Published:
- Journal Name:
- Abstract of Papers, 235th Electrochemical Society Meeting
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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